In the electrical industry it is often necessary to insulate specific electrical components prior to assembly. Heat curable epoxy compositions which are liquid at room temperature have been employed in the art as impregnating and insulating compounds for electrical components such as electrical coils. See U.S. Pat. No. 3,052,650 and U.S. Pat. No. 3,692,715. The epoxy compositions of U.S. Pat. No. 3,052,650 are formed of an epoxy resin, a polycarboxylic acid anhydride, and a tertiary amine catalyst.
Although the epoxy compositions of the art have proven useful to impregnate and encapsulate electrical components, the compositions of the art tend to suffer loss of physical and electrical properties due to water absorption when exposed to moisture containing environments. The resin compositions of the art also tend to require lengthy curing times and to volatilize during the curing process.
A need therefore exists for epoxy compositions which show improved retention of properties when exposed to moisture containing environments and which avoid the deficiencies of the resins of the prior art.